SOLUTION
Line 1 is given as
[tex]y=-2x+7[/tex]let's find the equation of line 2, it passes through points (2, 3) and (4, 4)
The slope is
[tex]\begin{gathered} m=\frac{4-3}{4-2} \\ m=\frac{1}{2} \end{gathered}[/tex]The slope of line 2 is 1/2
If the two lines are perpendicular, then the product of their slope will be = -1, that is
[tex]\begin{gathered} m_1m_2=-1 \\ slope\text{ of line 1 m}_1=-2 \\ slope\text{ of line 2, m}_2=\frac{1}{2} \\ -2\times\frac{1}{2}=\frac{-2}{2}=-1 \\ \end{gathered}[/tex]Since the product of their slope = -1
Hence Line 1 and Line 2 are perpendicular